termios support

[Eric Norum]

Following-up my previous note about termios support.

I think that the device-dependent output code for an  
interrupt-per-transmitted-character device like a standard UART could  
be as simple as the following two routines.

=============================================================
void
device_write_routine (int minor, char *buf, int count)
{
        UART->output_register = *buf;
        UART->control_register |= UART_TRANSMIT_INTERRUPT_ENABLE;
}

void
device_transmit_interrupt_routine (int vector)
{
        UART->control_register &= ~UART_TRANSMIT_INTERRUPT_ENABLE;
        rtems_termios_dequeue_characters (device_ttyp, 1);
}
=============================================================

I hope this pseudo-code is understandable......

---
Eric Norum                                 eric at skatter.usask.ca
Saskatchewan Accelerator Laboratory        Phone: (306) 966-6308
University of Saskatchewan                 FAX:   (306) 966-6058
Saskatoon, Canada.